Photoionization models of luminiscence and physical characteristics of planetary nebulae : BD +30 3639 and NGC 7293.

A photoionization model of the luminescence of planetary nebulae is described and applied to the planetary nebulae BD + 30 deg 3639 and NGC 7293. The intensities of the emission lines of basic chemical elements whose lines are observed in the UV, optical, and IR spectral ranges are calculated. The radial distribution of Ne, Te, n(H) and other parameters in the nebulae, as well as the continuum of the central stars beyond 912 A are found. The optical thicknesses of these nebulae at the frequencies of the Lyman continuum are derived, and precise abundances of the elements in the nebulae are determined.